Surface for grinding and crushing



' Patented Oct. 8., 1889.

A. P. STEPHENS. y .SUREAGE FOR. GRINDING AND GRUSHING.

(No Model.)

f UNITED STATES PATENT OFFICE.

ANSON P. STEPHENSfOF NEW BRUNSWICK, NEW JERSEY.

SURFACE FoR GR|ND|NG AND oRusHlNe.

SPECIFICATION forming part of `Lei-.ters Patent No. 412,558, dated October 8, 1889.

Application filed February 18, 1889. Serial No. 300,281. (No model.)

To all whom it may concern:

Be it known that I, ANsoN P. STEPHENS, of New Brunswick, in the county of Middlei sex and State of New Jersey, have invented an Improvement in Surfaces for Grinding and Crushing, of which the following is a specification.

Rolls for crushing stone and other materials have been made of cast-iron and also of steel; but in practice the surfaces are liable to become grooved circumferentially in consequence of the ore or other hard substance not being cracked, but remainingbetween the rolls, or such surfaces wear away unevenly in consequence of blow-holes and soft placesn the metal, and in cases where the rolls are adapted to catch and crush the mineral substances such mineral substances are liable to become pulverized too finely and the surfaces of the rolls or other grinding or cracking device, being of uniform hardness, do not offer angles or offsets for catching and cracking the stone or other material, and in cases where the surfaces have been corrugated or roughened the corrugations will wear off rapidly and cease to be useful.

I make my crushing or grinding rolls of alternate hardand soft materials in order that the softer portions of the material will wear away the most rapidly and l'leave the harder portions of the surfaces projecting to form knobs or protuberances that catch and crack the stone or other material between the two surfaces of the rolls.

In the drawings, Figure 1 is a section of a pair ofcrushing-rolls. Fig. 2 is a side eleva tion of one of the crushing-rolls. Fig. 3 is a sectional plan representing my improvement as adapted to a crushingmut and surrounding conical receptacle, and Fig. 4 is a vertical section of Crusher-jaws with my im provement. Y

I make use of -a body B of cast metal-such as cast-iron alone or with any suitable alloying metal and blocks or pieces A of steel or similar material-against or around which the iron of the body B is cast, It is preferable to make the blocks or pieces A of the proper size and shape and then to set them into the mold into which the metal is cast, so that such cast metal may run against or around the block, which may have been previously heated, and

such metal should be sufficiently hot to fuse and unite with the surfaces of the steel blocks, thereby holding such blocks firmly into the cast metal, and in effecting this the melted metal in a highlyheated condition may be run through the mold and overiow until the blocks become sufficiently heated.

According to the object for which the grinding or crushing rolls are made, so the blocks or pieces A may be closer together or farther apart, and in some portions of the rolls shown I have represented the steel blocks as coming close together, it being understood that in use the edges of the blocks A will be Worn away most rapidly, so as to form slight grooves or recesses between one block and the next for catching and cracking the ore or other material operated upon.

In the manufacture of these crushing or grinding rolls the casting may be allowed to Y cool slowly, so that the steel blocks A will be in a soft condition adapted to being turned, ground, or otherwise rendered sufficiently true for the purposes intended, after which the roll may be heated and the steel hardened or tempered to any desired extent.

It is usually preferable to consolidate the steel made use of for the blocks or pieces A by rolling or forging the same to render such steel more uniform in density and hardness, and when the surfaces of the rolls are made true and smooth before being used the castiron portions will wear away with sufficient rapidity to allow the steel pieces to project sufficiently for rendering the cracking or grinding operation the most efficient.

In eases where blocks or pieces of steel have been held within a cast-iron backing to form a stamp-head, such steelpieces have not been set closely together to form the active surface, and this cannot be effectively employed Vunless the steel pieces are melted at their inner end, so as to fuse with the castiron.

I do not claim stamp-heads in which the cast-iron receives and holds the steel faces or pieces of steel, as these have been used; but in reciprocating jaws or stamps the action is different to rolls, because in rolls the surface is liable to wear into deep or wide peripheral grooves or channels. This is prevented by my improvement, wherein the projections on the rolls cat-ch and crush hard substances that 1o of peripheral grooves, substantially as set forth.

2. Thegrinding-surface for crushing or grindinga-pparatus,composed of pieces of steel set closely together and held firmly in place by the inner surfaces being fused with and by the eastiron in Contact With them, substantially as speoied.

Signed by me this 14th day of February, 1889.

ANSON P. STEPHENS.

1Witnesses:

GEO. T. PINCKNEY, WILLIAM G. Morr. p 

